unusual period!!?

I usually bleed for 5-7days, with a 2-3 day period where I see brown bit no red, and with not much cramping since having my daughter.
This time there was no brown days before and I only bled for 2days. This has never happened.
Have you, who have had babies before, had something like this for implantation? I tested last Saturday, but test was-. Should I test again?